Tibial Component Subsidence in a Total Ankle System Comparing Standard Technique Versus a Hybrid Technique

Area of Science:

• Orthopedic surgery
• Biomedical engineering
• Arthroplasty research

Background:

• Total ankle arthroplasty (TAA) is a surgical option for end-stage ankle arthritis.
• Concerns exist regarding early loosening of low-profile tibial trays in fourth-generation TAA systems.
• A hybrid technique using a stemmed intramedullary tibial component and chamfer-cut talar component has been developed.

Purpose of the Study:

• To compare short-term outcomes of tibial components between a standard fourth-generation TAA system and a novel hybrid technique.
• To evaluate the incidence of tibial component subsidence and periprosthetic lucency in both TAA systems.

Main Methods:

• Retrospective study including 46 patients with a minimum 1-year follow-up.
• Comparison of a standard fourth-generation TAA system (n=25) with a hybrid technique (n=21).
• Analysis of tibial component subsidence, time to subsidence, revision rates, and periprosthetic lucency.

Main Results:

• No statistically significant demographic differences between the groups.
• Tibial component subsidence occurred in 8% of the standard group and 0% of the hybrid group (p=0.49).
• Periprosthetic lucency was observed in 32% of the standard group versus 9.5% of the hybrid group (p=0.08).

Conclusions:

• Both TAA systems demonstrated low rates of tibial component subsidence.
• The hybrid technique showed a trend towards reduced subsidence and lucency, though not statistically significant.
• Further research is needed to identify factors influencing early tibial component subsidence and implant failure.